emoji-stealer-mrf/steal_emoji_policy.ex

defmodule Pleroma.Web.ActivityPub.MRF.StealEmojiPolicy do
  require Logger
  @moduledoc "Detect new emoji and steal them"
  @behaviour Pleroma.Web.ActivityPub.MRF

  defp has_emojo(installed_emoji, str) do
    result = for emojo <- installed_emoji, elem(emojo, 0) == str, do: true
    length(result) == 1
  end

  @impl true
  def filter(%{"object" => %{"emoji" => foreign_emoji}} = object) do
    num_foreign_emoji = Kernel.map_size(foreign_emoji)

    if num_foreign_emoji > 0 do
      Logger.debug("#{num_foreign_emoji} EMOJI TO PROCESS")
      installed_emoji = Pleroma.Emoji.get_all()

      new_files =
        for {emojo_shortcode, emojo_url} <- foreign_emoji,
            !has_emojo(installed_emoji, emojo_shortcode) do
          Logger.debug("HANDLING EMOJO")

          cond do
            String.contains?(emojo_shortcode, "/") ->
              Logger.error("BAD EMOJO SHORTCODE: #{emojo_shortcode}")

            String.starts_with?(emojo_url, "https://") ->
              try do
                remote_emojo = HTTPoison.get!(emojo_url)

                if remote_emojo.status_code == 200 do
                  with {:ok, current_dir} <- File.cwd() do
                    new_file = current_dir <> "/priv/static/emoji/stolen/" <> emojo_shortcode <> Path.extname(emojo_url)

                    {:ok, file} = File.open(new_file, [:write])
                    IO.binwrite(file, remote_emojo.body)
                    File.close(file)
                    Logger.debug("SAVED EMOJO")
                    new_file
                  end
                end
              rescue
                e in RuntimeError -> Logger.error("FAILED TO QUERY REMOTE EMOJO #{emojo_url} #{e}")
              end

            true ->
              Logger.error("EMOJO COND FAIL #{emojo_shortcode} #{emojo_url}")
          end
          

        end

      Logger.debug("EMOJI FILES: #{inspect(new_files)}")

      if length(new_files) > 0 do
        Logger.debug("RELOADING EMOJI")
        Pleroma.Emoji.reload()
      else
        Logger.debug("NO EMOJI TO LOAD")
      end
    end

    {:ok, object}
  end

  @impl true
  def filter(object) do
    {:ok, object}
  end

  @impl true
  def describe, do: {:ok, %{}}
end